全文获取类型
收费全文 | 129篇 |
免费 | 7篇 |
国内免费 | 4篇 |
专业分类
林业 | 1篇 |
农学 | 2篇 |
72篇 | |
综合类 | 52篇 |
农作物 | 1篇 |
水产渔业 | 8篇 |
畜牧兽医 | 1篇 |
植物保护 | 3篇 |
出版年
2024年 | 2篇 |
2022年 | 3篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 1篇 |
2017年 | 3篇 |
2016年 | 2篇 |
2015年 | 4篇 |
2014年 | 5篇 |
2013年 | 6篇 |
2012年 | 7篇 |
2011年 | 7篇 |
2010年 | 7篇 |
2009年 | 10篇 |
2008年 | 17篇 |
2007年 | 16篇 |
2006年 | 13篇 |
2005年 | 10篇 |
2004年 | 10篇 |
2003年 | 4篇 |
2002年 | 2篇 |
2001年 | 3篇 |
2000年 | 1篇 |
1997年 | 1篇 |
1990年 | 1篇 |
排序方式: 共有140条查询结果,搜索用时 187 毫秒
61.
62.
63.
Protozoan response to addition of the bacteria Mycobacterium chlorophenolicum and Pseudomonas chlororaphis to soil microcosms 总被引:2,自引:0,他引:2
Protozoa are important predators of bacteria in soil and protozoan predation is one of the main factors responsible for the
decline of bacterial populations introduced into soil. Bacteria, however, are not equally susceptible to protozoan predation.
We have studied the response of indigenous protozoan populations to the introduction of the polychlorophenol-degrading bacterium
Mycobacterium chlorophenolicum PCP-1 (DSM 43826), and Pseudomonas chlororaphis (ATCC 43928), into soil microcosms. Introduction of P. chlororaphis to the soil resulted in a huge increase in the numbers of heterotrophic flagellates and naked amoebae during the first 8 days
of the experiment. Addition of M. chlorophenolicum to soil caused only a slight increase in protozoan numbers, which was similar to the increase caused by addition of water.
There was no indication that addition of M. chlorophenolicum to soil resulted in any increase in the number of protozoa able to feed on this bacterium. The number of colony forming units
(CFU) decreased rapidly in the treatment amended with P. chlororaphis cells, whereas there was no decrease in CFUs in the M. chlorophenolicum treatment. The only slight increase in protozoan numbers in the M. chlorophenolicum treatment, as well as the apparently low mortality rate of M. chlorophenolicum in the soil microcosms, coincided with significantly lower soil respiration in the soil microcosms amended with M. chlorophenolicum compared to those amended with P. chlororaphis. The results suggest that the indigenous soil protozoa did not graze on M. chlorophenolicum at all, presumably because it is not a suitable food source.
Received: 23 February 2000 相似文献
64.
本文通过盆栽试验初步研究了黑麦草 (LoliummultiflorumLam)对污染土壤中多环芳烃苯并 [a]芘动态变化的影响。盆栽试验设计 3种苯并 [a]芘处理浓度 ,分别为 1、10、10 0mgkg-1。将苗龄为 1周的黑麦草移植于受苯并 [a]芘污染的土壤中 ,同时设置有相同的苯并 [a]芘处理浓度但不种植物的对照试验。试验在2 0m3 的控温、控光的生长室内进行 ,土壤湿度维持在田间持水量的 6 0 %。通过 12 0d的温室盆栽试验 ,观察到土壤中苯并 [a]芘的可提取浓度随着时间逐渐减少 ,种植黑麦草加快了土壤中可提取态苯并 [a]芘浓度的下降。在 1、10、10 0mgkg-1苯并 [a]芘处理浓度下 ,黑麦草生长的土壤中苯并 [a]芘的减少率分别达 82 3%、74 0 %和 5 5 9%。结果还显示 ,随盆栽时间的延长 ,黑麦草根圈土壤中多酚氧化酶含量提高 ,这可能根圈土壤中可提取态苯并 [a]芘含量降低有关。黑麦草的地上部可以积累苯并 [a]芘 ,变幅在 0 0 6~ 3 6 0mgkg-1。初步认为 ,土壤具有缓解苯并 [a]芘污染的自然本能 ,促进黑麦草生长 ,增强土壤多酚氧化酶活性 ,可提高黑麦草对苯并 [a]芘污染土壤的修复能力。 相似文献
65.
P. Roberts 《Soil biology & biochemistry》2006,38(7):1812-1822
There is increasing environmental concern about the impact of endocrine disrupting chemicals (EDCs) on ecosystem sustainability and human health. Many EDCs are present within wastes which are routinely spread to land (e.g. biosolids). The aim of this study was to investigate the behaviour and fate of the EDC, 4-nonylphenol (NP), in a range of soils and to assess the potential risk it may pose to soil and freshwaters environments. We showed that NP was not persistent in soil, that NP mineralization was concentration-dependent and was stimulated by the addition of organic residues (e.g. biosolids, glucose, dead roots) but not by the presence of a rhizosphere. NP had no negative effect on soil respiration or plant growth unless present at extreme concentrations (?10,000 mg NP kg−1) and the uptake of NP by plants was very low. While NP was sorbed to the solid phase it could easily be leached from soil. Taking all of our results together, we conclude that the spreading of NP contaminated waste soil to soil probably poses a very low environmental risk to freshwater ecosystems and human health. 相似文献
66.
67.
从三个方面综述了蚯蚓对土壤污染的指示作用:(1)通过调查污染区土壤中蚯蚓种群的数量和结构反映土壤污染情况;(2)利用蚯蚓进行生态毒理风险评价,指示污染物对土壤生态系统可能造成的危害;(3)利用蚯蚓监测土壤污染。并阐述了蚯蚓对重金属的主要耐性机制:(1)脂质过氧化保护酶系统缓解氧化胁迫;(2)分隔、固定作用;(3)螯合解毒作用;(4)溶酶体和细胞质粒抑制重金属活性。同时,分析了蚯蚓强化污染土壤修复的潜力,认为蚯蚓可以通过改善土壤理化性质、增强微生物活性、改变污染物的活性等强化污染土壤的生物修复过程。 相似文献
68.
Marco Derudi Gianluca Venturini Giorgio Lombardi Giuseppe Nano Renato Rota 《European Journal of Soil Biology》2007,43(5-6):297
The effectiveness of the SS-SBR (Soil Slurry – Sequencing Batch Reactor) process for the remediation of soils contaminated by several organic pollutants has been evaluated. Experimental tests have been performed on two different soils, a spiked one and an industrial aged soil. The spiked soil, artificially contaminated, has been prepared trying to simulate the pollution of an industrial aged soil in terms of number and kind of contaminants. PAHs (Polycyclic Aromatic Hydrocarbons) and phenols degradation has been particularly investigated because they are considered persistent and recalcitrant. Concerning the spiked soil, removal efficiencies higher than 95% in 6 to 9 weeks have been found for all the pollutants, except for five-rings PAHs; however, these compounds were partly removed in 11 to 13 weeks. Good results have been achieved also for the industrial aged soil with a maximum removal of about 80% in 7–8 weeks. To enhance the pollutants degradation, trying to obtain a faster remediation, the biological treatment has been combined with a chemical oxidation with ozone. The best degradation effectiveness of the combined process has been obtained applying the ozonation after few days of the biological treatment. Therefore, a combined biological and chemical treatment allowed to markedly improve the remediation of contaminated soils. 相似文献
69.
酸性条件下氮素形态对西红柿根系释放羟基的影响 总被引:1,自引:0,他引:1
为研发酸化土壤的生物修复技术,本文用水培实验和电位滴定方法研究了酸性条件下氮素形态对西红柿根系释放羟基的影响,结果表明,在初始pH为4.0、NO3-/NH4+ 比为15:1、5:1、1:1和1:5的营养液中,由于西红柿对NO3--N的偏好吸收导致根系释放羟基,培养液pH升高。培养1周后4个NO3-/NH4+ 比培养液pH分别升高了1.60、1.15、0.57和0.29,与西红柿对NO3--N的吸收量和羟基释放量的大小一致。当西红柿生长在初始pH为5.0营养液中时,仅NO3-/NH4+ 比为15:1和5:1体系中西红柿根系释放羟基,导致培养液pH升高;在NO3-/NH4+ 比为1:1和1:5体系中西红柿根系释放质子,导致培养液pH降低。初始pH5.0条件下西红柿吸收的NO3--N低于初始pH4.0条件下的,其根系释放的羟基量也低于pH4.0体系中的。这些结果说明低pH条件有利于西红柿对NO3--N的吸收,西红柿根系也会释放更多的羟基。因此可以根据西红柿在强酸性条件下对NO3--N的偏好吸收和根系释放羟基的特点对酸化土壤进行生物修复。 相似文献
70.
多环芳烃污染土壤真菌修复进展 总被引:6,自引:0,他引:6
多环芳烃是一类具有致癌、致畸、致突变效应的化合物,主要通过生物质和化石燃料的不完全燃烧产生,过量的排放可能导致土壤污染。现有多环芳烃污染土壤的生物修复大多利用细菌的降解功能,真菌的修复潜力尚未被充分认识。真菌是土壤生态系统的重要组成部分,具有极高的多样性。多种真菌,主要是担子菌和子囊菌具有降解多环芳烃的能力,它们通过细胞内的细胞色素P450氧化酶、细胞外的木质素水解酶及胞外聚合物系统作用于多环芳烃;某些真菌与植物形成共生菌根,以协同方式实现污染物的降解。由于真菌降解多环芳烃的特点,其在减少土壤高环多环芳烃含量、降低多环芳烃毒性方面具有独特的优势。本文综合介绍了多环芳烃降解真菌的多样性和降解机制,对现有的真菌土壤修复技术进行了总结,针对目前真菌修复中存在的问题作了进一步讨论,并对真菌修复的未来发展趋势提出了展望。 相似文献